Fire crews from Aberbargoed and Caerphilly attended a fire on a first floor windowsill of a property in Maesycwmmer on Saturday, April 3.
The small fire had been extinguished by the time crews arrived at the two-storey detached house on Thomas Street, Maesycwmmer, but is believed to have been set deliberately.
South Wales Fire and Rescue Service conducted an inspection upon arrival at around 1.21pm.